[❔ other question] Basic Rendering Issue

[Vmbundu]

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• [🐛 bug report]
• [🔨 compilation issue]
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Summary

Almost everytime I render a scene, I get a black screen. The only scene I could somewhat render is a sphere within a constant emitter.
I get a Sampler runtime error when I changed the variant from scalar to packet in an attempt to circumvent the problem.

System configuration

For bug report, please enter information regarding your system configuration<- [remove this]

• Platform: Ubuntu 18.04.6
• Compiler: CMake/Clang 3.22.1
• Python version: Python 3.9.7
• Mitsuba 2 version: newest
• Compiled variants:
  • scalar_rgb
  • 'scalar_spectral'
  • 'packet_rgb'

Description

I ma attempting to render scenes with different shapes and with bsdf that are not only "diffuse" but ot no avail.

Steps to reproduce

For bug report, please enumerate the steps to follow in order to reproduce the issue <- [remove this]

1. After compilation, a created a simple xml with a sphere is constant emitter
2. Ran a python file similiar to render_scene.py
3. I produced the scene of interest
4. I changed the bsdf to dielectric and the scene would render black
5. I changed the variant from scalar to packet and recompiled it
6. Ran the python script again and got a sampler error ... RuntimeError: ​[Sampler] Assertion "m_sample_index < (m_sample_count / m_samples_per_wavefront)" failed in /home/vbundu/mitsuba2/src/librender/sampler.cpp:31